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Polyimides and Process for Preparing Polyimides Having Improved Thermal-Oxidative StabilityPolyimides and the process for preparing polyimides having improved thermal-oxidative stability derived from the polymerization of effective amounts of one or more of the polyamines such as the aromatic diamines, one or more of the tetracarboxylic dianhydrides and a novel dicarboxylic endcap having formula with an R1 group of either hydrogen or an alkyl radical of one to four carbons, an R2 group of either OH, NH2, F, or Cl radical, an R3 group of either H, OH, NH2, F, Cl or an alkylene radical, an R4 group of either an alkyl, aryl, aryloxy, nitro, F, or Cl radical, and/or an R5 group of either H, alkyl, aryl, alkoxy, aryloxy, nitro, F, or Cl radical. The polyimides are useful particularly in the preparation of prepegs and PMR composites.
Document ID
20010111095
Acquisition Source
Glenn Research Center
Document Type
Other - Patent
External Source(s)
LEW-16987-1
Authors
Mary Ann B Meador
(Glenn Research Center Cleveland, United States)
Aryeh A Frimer
(Glenn Research Center Cleveland, United States)
Date Acquired
August 20, 2013
Publication Date
October 16, 2001
Publication Information
Publisher: United States Patent and Trademark Office
Subject Category
Nonmetallic Materials
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-6,303,744
Patent Application
US-Patent-Appl-SN-535663
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